Friedrich marx



UNITED STATES ATENT nricn.

FRIEDRICH MARX, OF BERLIN, GERMANY.

PROCESS OF MANUFACTURING METALLIC ELECTRODES FOR BATTERlES.

SPECIFICATION forming part of Letters Patent No. 425,335, dated April 8,1890. Application filed December 30, 1889. Serial No. 335,422. (Nomodel.)

To a whom, it may concern:

Be it known that I, FRIEDRICH MARX, a subject of the King of Prussia,German Emperor, and a resident of Berlin, No. 91 Grossbeeren Strasse, inthe Kingdom of Prussia, German Empire, have invented a certain new anduseful Process of hlanufacturing Metallic Electrodes, of which thefollowing is an exact description, and for which I have applied forLetters Patent in Germany on the 21st of November, 1889.

The method of manufacturing metallic .electrodes in use up till nowconsisted in working into the required form the metal obtained by asmelting process and then placing the same into the battery.

I have observed that the working effect of metallic electrodes may beconsiderably increased by avoiding the smelting process in theirmanufacture, and, instead, depositing the metal by electrolysis orprecipitation by other metals in a loose state. I base my process on thefact that the metals gained in the smelting process, on account. oftheir mechanical compactness and dense molecular combination, arecapable of resisting chemical actions to a considerable extent, andconsequently the electrolyte can only operate slowly on the same. If, onthe other hand, the metal for the electrode be obtained by precipitationwith other metals or electrolysis, a loose mass, almost of a spongynature, is gained, which is easily attacked by chemical reagents. If,now, the metal gained by electrolysis or precipitation with other metalsbe used as electrodes for galvanic batteries, the current generated bythe battery will be much stronger than those batteries in which themetal employed has been obtained by the smelting process, for the reasonthat the electrolyte can combine more thoroughly with the electrodes,and thus the chemical reaction will take place more vigorously.

Of course the decomposition of a certain amount of metal will onlyproduce the corresponding amount of electricity, so that the sum of theamount of-electricity generated remains the same in both cases, whetherthe electrodes are made of metal obtained by the smelting orelectrolytical process or that of precipitation by other metals. Theadvantage of the presentinvcution,however, is that electrodes of metalgained by the latter process, on account of the increased energy of thechemical reaction, will be used up or decomposed in much shorter time,so that the batteries need not to be so large as was formerly necessary,while the strength of the current does not get less.

It need hardly be mentioned that the electrodes must be renewed moreoften.

For the practical application of my invention I proceed in the followingmanner: The porous loose mass of metal gained by the electrolyticprocess or by precipitation with other metals is first carefully washedto clean it of any salts which it may contain and to prevent lateroxidation. The metal is then either rolled or hammered to a concretemass, which may then be coated with plumbago or metallic oxides in orderto exclude the oxygen of the air. It is often advantageous to roll intothe mass a woveu-wire fabric or rough metal plate, which, if necessary,may be used to carry the connection binder.

A further modification which may be advantageously employed in thepractice consists in depositing the metal which is to form the electrodedirectly on a conductor, (metal plate,) to which it is fixed by rollingafter having been washed as above described. The mechanical treatment isof importance in so far as by this means the electrode becomes capableof resistance to a certain extent, and

then again the oxidizing effect of the air is.

diminished, because the surface of the metal will be made denser by themechanical pressure.

In the case of zinc it is advantageous to add quicksilver, which isaccomplished by adding a soluble quicksilver salt to the electric bathin the one case or by adding metallic quicksilver to the precipitatedmetal.

As an example, showing how much stronger electrodes manufactured on thisprinciple work, it may be mentioned that an ordinary battery of iron andcarbon in a solution of common salt gave the following result: 0.1ampere and 0.35 volt, (the iron having been gained by the smeltingprocess,) while a battery of the same size in which the iron wasgainedby electrolytic process and then worked mechanically gave theresult: 0.9 am pore and 0.85 volt;

I am aware that metals gained by the electrolytic process have beenWorked up for electrodes; but this was always achieved by first melting,then casting and rolling the same into the required form. The gist ofthe present invention consists in avoiding the smelting process entirelyand to use the loose chemically-active metal after having been Workeddirectly as an electrode.

The process above described may be employed for every sort of metalWhich has up till now been used for electrodes; but practice has provedthat the manufacture of zinc, iron, and copper electrodes maybeconducted on my principle with particular advantage.

Having thus fully described and ascertained the nature of my saidinvention, What I desire to secure by Letters Patent of the UnitedStates is 1. The process of manufacturing metallic electrodes forgalvanic batteries by purifying from the presence of salts the metallicdeposit obtained by the electrolytic process or by precipitation Withother metals andthen working mechanically the mass so purified into therequired form, substantially as specified. 2. The process ofmanufacturing metallic electrodes for galvanic batteries by purifyingfrom the presence of salts the metallic deposit obtained by theelectrolytic process or by precipitation with other metals and thenrolling into the mass so purified a wire Woven fabric or metal plate, inthe manner substantially as described. I

8. The process of manufacturing metallic electrodes for galvanicbatteries by electrolytically precipitating or with other metalsprecipitating the metal on a conducting-plate, then Washing the same andfixing it on the plate by rolling, in the manner described.

In Witness whereof I have hereunto set my hand in presence of tWoWitnesses.

FRIEDRICH MARX. Witnesses:

EUSTACE HOPKINS, PAUL AULIoH.

